The proposed studies, an outgrowth of previous studies in our laboratory, will utilize ion-exchange electrodes to further define and quantify the binding of Ca ions and Mg ions to the serum proteins, particularly albumin. Specific aims are: (1) To define the thermodynamic properties of calcium-binding to serum albumin in normal subjects and in patients with: (1) stable cirrhosis, (2) progressive cirrhosis, (3) chronic active hepatitis, and (4) fulminant hepatitis. Our hypothesis is that the diseased hepatocyte may synthesize faulty albumin as suggested by previous calcium-binding studies in this laboratory. (2) To further define the relationship between calcium-binding and specific protein conformational states in each of the above groups using circular dichroism (CD) and optical rotatory dispersion (ORD). The hypothesis to be tested is that, upon dissociation of the last Ca ions from the albumin molecule (as in severe hypocalcemia), the albumn molecule loses all affinity for Ca ions (K'a equals O), a phenomenon which we have termed "The Clam Effect". We postulate that "The Clam Effect" is related to the closng of an alpha-helix upon dissociation of the last Ca ions from the albumin molecule. (3) To continue similar studies with highly purified crystalline human albumin, using Ca ions electrodes and circular dichroism. (4) To similarly study the binding of magnesium, as outlined above for calcium, using an ion-exchange ("water hardness") electrode with about equal selectivity for Mg ions and Ca ions. A Ca ions electrode will be sued as the reference electrode in these studies for subtraction of the Ca ions component of the total electrode potential.